Cable-stayed bridges have proven to be economical for spans in the range of 1,000 ft. They are economical because of the lightness of the bridge deck, which is supported by closely-spaced cables that are designed to carry the horizontal component of the cables, and because they reduce the amount of bending, due to their short spans. However, the lightness of the deck structure also brings with it the disadvantage of a relatively flexible deck which is less able than a stiffer structure to spread the live load over a larger area.
Because of this flexibility, the cable girder (i.e., the longitudinal girder where the bottom ends of the cables are anchored) has to be designed to be stiff enough to distribute the live loads over several cables. Thus, the smaller the differential deflection, the lighter and more economical the longitudinal cable girder will be.
Stay cables are also subject to corrosion. Although protection by cement grout within an enclosure pipe is commonly provided, there have been questions on the grout's competency in protecting the cables against corrosion, because of the grout's tendency to crack due to shrinkage and cable elongation under live loads.